Blog Log in Get Started Free

Physics MCQs for NEET — Practice Questions with Answers

Practice free Physics NEET multiple-choice questions online with instant answers and detailed explanations. No login required.

All Physics Chemistry Botany Zoology

Chapter Language Difficulty Show only questions I answered incorrectly Register free to filter questions

● ● ● ● ●

Electron volt is a unit of

Potential

Charge

Power

Energy

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(d) Electron volt is the unit of energy.

● ● ● ● ●

In an electron gun, the electrons are accelerated by the potential V. If e is the charge and m is the mass of an electron, then the maximum velocity of these electrons will be

$\frac{2 eV}{m}$

$\sqrt{\frac{2 eV}{m}}$

$\sqrt{\frac{2 m}{eV}}$

$\frac{V^{2}}{2 em}$

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(b) $eV = \frac{1}{2} {mv}^{2} \Rightarrow v^{2} = \frac{2 eV}{m} \Rightarrow v = \sqrt{\frac{2 eV}{m}}$

● ● ● ● ●

The idea of matter waves was given by

Davisson and Germer

de-Broglie

Einstein

Planck

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(b) The idea of matter waves was given by de-Broglie.

● ● ● ● ●

Wave is associated with matter

When it is stationary

When it is in motion with the velocity of light only

When it is in motion with any velocity

None of the above

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(c)

According to the de-Broglie hypothesis, a wave is associated with the matter when it is in motion i.e. it is in motion with a velocity.

● ● ● ● ●

The de-Broglie wavelength associated with the particle of mass m moving with velocity v is

h/mv

mv/h

mh/v

m/hv

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(a) $λ = \frac{h}{p} = \frac{h}{mv}$

● ● ● ● ●

A photon, an electron, and a uranium nucleus all have the same wavelength. The one with the most energy:

Is the photon

Is the electron

Is the uranium nucleus

Depends upon the wavelength and the properties of the particle

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(a)

$λ = \frac{h}{mv} = \frac{h}{\sqrt{2 mE}} ∴ E = \frac{h^{2}}{2 {mλ}^{2}}$

$λ$ is same for all, so $E \propto \frac{1}{m}$ . Hence energy will be maximum for particle with lesser mass.

● ● ● ● ●

A particle which has zero rest mass and non-zero energy and momentum must travel with a speed:

Equal to c, the speed of light in vacuum

Greater than c

Less than c

Tending to infinity

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(a) Particle is photon and it travels with the velocity equal to light in vacuum.

● ● ● ● ●

When the kinetic energy of an electron is increased, the wavelength of the associated wave will

Increase

Decrease

Wavelength does not depend on the kinetic energy

None of the above

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(b) $λ = \frac{h}{p} = \frac{h}{\sqrt{2 mE}}; ∴ λ \propto \frac{1}{\sqrt{E}}$ ( h and m = constant)

● ● ● ● ●

If the de-Broglie wavelengths for a proton and for a $α$ -particle are equal, then the ratio of their velocities will be

4 : 1

2 : 1

1 : 2

1 : 4

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(a) $λ = \frac{h}{m_{1} v_{1}} = \frac{h}{m_{2} v_{2}} ∴ \frac{v_{1}}{v_{2}} = \frac{m_{2}}{m_{1}} = \frac{4}{1}$

● ● ● ● ●

The de-Broglie wavelength $λ$ associated with an electron having kinetic energy E is given by the expression

$\frac{h}{\sqrt{2 mE}}$

$\frac{2 h}{mE}$

2mhE

$\frac{2 \sqrt{2 mE}}{h}$

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

(a) $\frac{1}{2} {mv}^{2} = E \Rightarrow mv = \sqrt{2 mE}; ∴ λ = \frac{h}{mv} = \frac{h}{\sqrt{2 mE}}$

Ready to ace NEET?

Free access · No credit card required

Browse All Questions Create Free Account

Frequently Asked Questions

Yes. You can attempt every Physics question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.

No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.

The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.